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current livecd is based on minifo

Advantages

• each module mounts as an overlay of the previous
• no requirement for ramdisks and symlinks etc.

Issues

• mini-fo is _BUGGY_.
• complex
• maintenance
• divergence (hardware detection)
• different kernel
• different X
• limited architecture support
• rsyncablity

New design (for hoary):

writable ( mini-fo )

• -> device mapper snapshots

  • copy on write at block level

compression ( cloop )

• -> want to use cloop

  • currently doesn't play well with device mapper (wrong blocks, corruption, badness)

hardware detection ( knoppix )

• -> switch to hotplug

build system ( morphix )

• -> debian-installer & custom bits

  • need to better handle netcfg w/o dhcp issues.
• other architecture support comes for (hopefully) free.
  • addressed by debian-installer

kernel ( 2.6.7+patches vs 2.6.8.1 )

• -> unifying: add cloop to stock kernel.

X ( mkxf86conf )

• Xorg config ubuntu packages (using debconf)

New Fun Stuff

• persistant data (use a persistant device for COW)
• arbitrary storage ("it's a block device")
• debian-installer customization
• combined liveCD and install media

Misc notes

SquashFS is a read-only filesystem, which violates the design criteria.

From Juanje Tue Apr 5 14:06:42 +0100 2005 From: Juanje Date: Tue, 05 Apr 2005 14:06:42 +0100 Subject: Squashfs, ro, and so on Message-ID: <20050405140642+0100@https://www.ubuntulinux.org>

Current System:

ext3 image (rw) + cloop (ro) = cloop image (ro)

cloop image (ro) + blocks dev (rw) + device mapper snapshots = semi-rw filesystem

Proposal:

Squashfs (ro) + dir (rw) + unionfs = semi-rw filesystem

Reasons:

Cloop = Buggy, slow, inefficient

Squashfs = Stable, fast, very efficient, it suports more architectures

Unionfs extras = you can mount directories, it's no necessary to be a bloks dev. That open a lot of posibilities more than with just blocks devices'

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